Multi-target decision method for limiting short circuit currents in receiving-end electrical network

Abstract

The invention discloses a multi-target decision method for limiting short circuit currents in the receiving-end electrical network. The method comprises steps that, an impedance matrix of a breaking line for the receiving-end electrical network is monitored, and self impedance sensitivity of a breaking m back line having n exceeding standard sites is figured out; according to short circuit current exceeding standard degrees of the various exceeding standard sites, weighted self impedance sensitivity of limit short circuit currents of any breaking line for all exceeding standard sites in the receiving-end electrical network is acquired; a power flow equation of the receiving-end electrical network is solved through utilizing a Newton Laphson algorithm to acquire Thevenin equivalent parameters; sensitivity indexes of the breaking line for system safety is acquired according to the Thevenin equivalent parameters and boundary conditions for static state voltage stabilization margin; a multi-target model is established, the Pareto optimal solution set is figured out, and optimal broken line combination for limiting short circuit currents of the various exceeding standard sites is acquired. The method can satisfy multi-target decision requirements for integrated optimum effects of short circuit current limit and integrity and safety of the system.

Description

technical field [0001] The invention relates to the technical field of electric power systems and automation thereof, in particular to a multi-objective decision-making for limiting short-circuit current of a receiving-end power grid. Background technique [0002] With the rapid development of my country's power grid, the power load has increased rapidly, the scale of the power grid has continued to expand, and the 500kV (kilovolt) backbone grid has been initially formed. However, due to the operation of the electromagnetic ring network of the 500kV power grid and the 220kV power grid, the relatively concentrated load, the tight grid structure, and the dense distribution of power sources have caused the short-circuit current level of the grid to increase rapidly, which has seriously affected the safe and stable operation of the entire grid. The current has approached or may even exceed the rated breaking capacity of the circuit breaker, and effective measures must be taken t...

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Problems solved by technology

How to maintain the integrity of the main network and the security of the system as much as possible while satisfying the short-circuit current limitation effect is significant, and no effective multi-objective decision-making scheme has been proposed yet.

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